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- perfectly inelastic different mass 2.mp4

Credits

Author: Leong Tze Kwang, Lim Beng Choo

Document Brief: Title: "Tracker 4/5 Perfectly Inelastic Collision with Different Masses by Leongster"

This document examines a 4/5 perfectly inelastic collision scenario where two objects of different masses collide and stick together post-collision. The focus is on momentum conservation, energy dissipation, and the dynamics of perfectly inelastic collisions.

Study Guide:

Objective: Analyze a 4/5 perfectly inelastic collision involving objects of unequal masses, emphasizing momentum conservation and energy loss.

Key Concepts:

1. Perfectly Inelastic Collisions:

   • Collisions where the objects stick together after impact, resulting in maximum energy loss compatible with momentum conservation.

2. Conservation of Momentum:

   • The total momentum before and after the collision remains constant: .

3. Energy Loss:

   • A significant portion of the kinetic energy is converted to other forms, such as heat, sound, and deformation.

4. Final Velocity Calculation:

   • The shared velocity after collision is .

Experiment Overview:

• Setup: Two objects of differing masses are allowed to collide on a frictionless surface, sticking together post-collision. The motion is tracked using video analysis tools like Tracker.

• Procedure:

  • Record initial velocities of both objects and their shared velocity after collision.

  • Verify momentum conservation by comparing pre- and post-collision momentum.

  • Calculate the percentage of kinetic energy lost.

• Observation Points:

  • The shared velocity of the combined masses.

  • The amount of kinetic energy dissipated.

Questions to Consider:

1. Why does the combined mass move with a single velocity post-collision?

   • Answer: Momentum conservation dictates a single resultant velocity when the objects stick together.

2. How is energy loss calculated in this scenario?

   • Answer: By comparing the total initial kinetic energy with the total final kinetic energy: .

3. What role do the masses of the objects play in the final velocity?

   • Answer: The relative masses determine the distribution of momentum and thus the final velocity of the combined mass.

Applications:

• Understanding collisions in vehicle safety and crash analysis.

• Teaching momentum and energy conservation principles.

• Studying real-world perfectly inelastic events, such as collisions involving sticky or deformable objects.

FAQ:

1. What is a perfectly inelastic collision? A collision where the colliding objects stick together after impact, moving as one unit.

2. What does 4/5 mean in this context? It signifies that most, but not all, kinetic energy is lost, leaving only 1/5 of the initial energy in the system’s motion.

3. Why is momentum conserved but not kinetic energy? Momentum conservation is a fundamental law of physics, while kinetic energy is not conserved due to energy transformation into heat, sound, or deformation.

4. How does the mass ratio affect the outcome? Larger mass differences result in final velocities closer to that of the more massive object.

5. Can this model predict real-world outcomes? Yes, it provides a framework for analyzing collisions in many practical scenarios, from vehicular impacts to material testing.